Stoker for underfeed furnace-grates.



F. E. DAVIS. STOKER FOR UNDBRFEED PURNACE GRATES. PPLICATION FILED SEPT. 4, 1912. 1,085,248. Patented Jan. 27, 1914.

3 SHEETS-SHEET 1.

x I l l I r l l l II www AN, MN @A MU.

APPLICATION FILED SEPT. 4, 1912.

Patented Jan. 27, 1914,

3 SHEETS-SHEET 2.

APPLIUATION FILED SEPT. 4, 1912.

Patented Jan. 27, 1914.

s SHEETS-SHEET s.

@NNN

rlfnnunnhon' FRED E. DAVIS, OF'MORGAN PARK, ILLINOIS.

STOKEB. FOR UNDERFEED FURNACE-GRATES.

Specification of Letters` Patent.

Patented Jan. 27, 1914.

Application filed September 4, 1912. Serial N o. 718,545.

To all whom 'it may concern Be it known that I, FRED E. DAVIS, a citizen of the United States, and a resident of Morgan Park, county of Cook, and State of Illinois, have invented'certain new and useful Improvements in Stokers for Underfeed F urnace-Grates, of which the following is a full, clear, and exact description.

The invention seeks to provide an efficient mechanical stoker for supplying coal in successive portions to an under-feed grate, coal being delivered from beneath in a vertical direction and through the center of the grate, so as to fall away or be distributed evenly at all sides without marked obstruction or banking.

The invention consists in the features of improvement hereinafter set forth, illustrated in the preferred forms in the accompanying drawings and more particularly pointed out in the appended claims.

In the drawings, Figure 1 is a vertical, central section of the improved stoker taken on the line 1 1 of Fig. 2. Fig. 2'is a verti- Cal section on the line 2 2 of Fig. l. Fig. 3 is a horizontal section on the line 3 3 of Fig. 1. Fig. 4: is a view similar to Fig. 1, illustrating a modified form. Fig. 5 is a vertical sect-ion on the line 5 5 of Fig. 4. Figs. 6 and 7 are views similar to Figs. 1 and 4, respectively, showing the shovels of the stoker in changed positions.

rl'he improved stoker comprises a feed chute having a vertical delivery portion terminating in a vertical exit pipe located beneath a central opening of the grate, and a series of feathering shovels with means for propelling and guiding the shovels in an endless path and arranged to move the shovels through the feed chute and to Withdraw the same from the ver-tical portion thereof directly beneath the terminal exit pipe, the object being to feed the coal in successive portions up through the vertical exit pipe beneath the center of the feed grate, so that the fresh coal is distributed evenly without banking. In this Way, fresh coal is fed beneath the burning coal on the grate and is not exposed at the surface of the fire, so that the gases discharged from the fresh coal are consumed and back tiring through the feed chute is prevented.

Both modications are shown in simple form, adapted for the common house furnace. In the construction illustrated, the fire pot 10 with its usual brick lining 11 is sustained upon a casing 12 which forms the ash pit of the furnace. The Stoker is arranged within the ash pit and the casing therefor comprises side Walls 13 and curved top and bottom pieces 14 and 15. Through bolts 16 unite the sides 13 and extend through square spacing bars 17 that abut against or are suitably secured to the outer faces of the curved top and bottom pieces 14 and 15.

The conveyer or feed chute of the Stoker inthe form show-n in F igs. 1 to 3, inclusive, extends along the ioor of the Stoker casing and upwardly in vertical direction at one side thereof, the chute terminating in a vertical exit pipe 18. The latter is arranged beneath and leads to a central opening in the grate 19 of the fire box 10. The grate 19 comprises suitable bars arranged symmetrically about its central opening. The feed chute is formed by fianges- 20 fixed to and project-ing inwardly from the curved bottom piece 15 of the stoker casing and arranged in parallel vertical planes. At their upper ends, the ianges 20 and the bottom piece 15 lie in the planes of or merge into the Walls of the exit pipe 18. The coal is delivered to the lower portion of the conveyer or feed chute in any suitable manner. In the construction shown, a hopper 21 is formed upon one side of the Stoker casing. At its upper end, the hopper is provided with a tight fitting lid 22. The lower end ofthe hopper opens into the conveyer or feed chute of the Stoker and is preferably provided with a sliding valve 23, by which the movement of the coal from the hopper to the feed chute may be regulated.

The coal is carried through the conveyer chute and is delivered to the exit pipe by a series of shovels 24. These shovels are preferably quadrant-shaped and are each mounted at one corner upon a transverse pivot or axle 25. The several axles, in the form shown in Figs. 1, 2 and 3, are mounted on a carrier comprising a series of chain links 26. The shovels are propelled through the feed chute by a pair of sprocket wheels 27 which are fixed to a transverse shaft- 28 and are provided with notches or seats-t0 receive the projecting ends of the axles 25. The shaft 28 is arranged on one side of and slightly below the mouth of the exit pipe 18 and, in the form shown, is journaled in suit-- able bearings in the si-'le Walls 13 of the Stoker casing and in the side walls of the ash pit 12. This shaftmay be driven in any position as they suitable manner. In the form shown, it is provided at one end with a large spur gear 29 which meshes with asmaller gear 30 on the end ofa drive shaft 31- This shaft is journaled in suitable bearings 32 mounted on the upper portion of the ash pit on one side of the ire box, by a 1crank handle or the like whenever a fresh supply of coal is to be fed to the grate.

EachA of the shovels 24 has a straight front face, that preferably lies in the plane of the axis of the corresponding axle 25. The bottom of. each shovel is preferably struck in a curve from its suspension axle, While its back portion is reversely curved to accomplish the nesting of thel adjacent shovels practically within the peripheral outlines of the sprocket wheels 27 as the shovels are passed over the upper portions of these wheels. The greater portion of the corner of the shovel near its-axial pivot is struck ona curve from its axis,`but adjacent the straight front face ofthe shovel, the corner portion is provided with an oset nose 33. The connecting chain links 26 which extend between the transverse axles 25 are preferably arranged between. the end faces of the shovels and the inner faces of the sprocket wheels 27, as shown in Figs. 2 and 3, the ends of the links filling the spaces between the shovels and the chain wheels to hold the shovels against lateral play. Preferably, as

shown, the projecting ends of the transverse' axles 25 are provided with anti-friction rollers 34, which seat within the notches'of the driving chain wheels 27.

To guide and hold the shovels in proper pass through the conveyer chute, a pair of pilot wheels 35 are provided. These wheels are mounted on an axle 36 which is concentric with the curved floor of the conveyer chute formed bythe part 15. In the const-ruction shown, the axle 36 is sustained upon brackets 37 (see Fig. 2) which are fixed to. and extend inwardly from the side walls 13 of the stoker casing. These guiding or pilot wheels 35 are provided with seats 38, four in number in the form shown, which are suitably shaped to engage the backs and rounded corner portions of the quadrant-shaped shovels. Between these not-ches, the peripheral portions of the pilot or guiding wheels are circular.

On reference to Fig. 1, it is seen that the upper shovels, as they swing over the shaft 28, hangin close relation from their sustaining axles 25 and nest snugly together between the driving V sprocket wheels 27. 0rdinarily,the topmost shovel, for example, would tend to turn axially by gravity until in balance from its point of support, whereas, the shovel is constrained to keep the position shown, because held in such position by contact of itsback with the bottoni-of i the shovel form next in advance. The same and the shaft is rotated scribed,

upreach nearer in the side of the casing.

holds true as the shovel progresses with the turn of the sprocket wheels 27 until a position is reached about opposite the outlet of the hopper 21, where the shovel passes from the drive wheels and is received upon the guiding or pilot wheels 35. At this point, the gradual advance of the shovel brings it to a position with its straight face down, as shown, and in which state the shovel must tend to topple, except forthe presence of the projecting nose on the rounded corner of the shovel and hich corner at this time engages one pair of seats in the guiding or pilot wheels 35. In this position, the projecting nose coperates with the peripheries of the pilot wheels to prevent the downward turning or toppling of the shovel, so that the latter 1s held in proper position to sweep past. the mouth of the hopper 21, and through the lower portion of the feed chute to engage and carry ona portion of coal. Anytendency to swingin reverse direction, as the shovel engages the portion of coal it is to move, finds immediate check because of the contact of the sho-vel back with the sloping portions of the seats 38 of the guiding pilot wheels. Under impulse of the rotating drive wheels 27, the chain links transfer the cross axles andshovel from the drive Wheels onto the pilot wheels which latter, as deserves to project each shovel properly into the feed chute and to hold it in position as it passes therethrough. It should be noted that as each shovel engages the pilot wheels, the chain links `connected thereto are in alinement, as indicated in dotted lines in Fig. 1, so that the shovel is kept securely in the seats of the pilot wheels, despite gravity. The face or front of each shovel describes something of a sweep in descent and servesto subtend the space from its pivot axle to the bottom of the feed chute, so that it scoops the full portion of coal accumulated therein.

As the shovels ascend through the vertical portion of the feed chute, they gradually apone another, as shown, and at this point, the nose 33 of each shovel acts as a guard to prevent the passage of coal inwardly between the corresponding shovel and the one next in advance. Any quantity of coal confined in excess between successive shovels in the vertical portion of the feed chute must tend to stall or break the apparatus. To prevent this, a safety valve 39 is held by a spring 40 over a vent opening'll This valve can be thrust open against the stress of its spring to discharge any surplus coal confined between two shovels as they arrive near the entrance to the exit pipe 18. j

The pilot wheels 35 are properly located to insure the travel of the shovels 24 nearly in right line as they ascend and fully arrive at the mouth of the exit pipe 18. As the shovels pass through this vertical discharge end of the conveyer chute, they are conveyed by the links from the pilot wheels 35 back onto the drive wheels 27. As they are so transferred, the rollers 34 on the ends of the transverse axles 25, engage parallel guide flanges 42 fixed to the side walls 13 of the Stoker casing. These guide flanges hold the upper corners of the shovels in proper `position as they pass through the vertical discharge end of the conveyer chute, while the rims of the pilot wheels 35 contact with the lower corners or tips of the shovels at this time. In this way, each shovel is held square to its work as it passes upwardly through the vertical portion of the conveyer chute and pushes its charge of coal upward into the mouth of the exit pipe18. Each shovel accomplishes this delivery during its upward rise, but at a point near the mouth of the exit pipe, it must be allowed to swing clear in retreat from any obstructive encounter with said pipe. As it starts to recede or swing inwardly upon its axle 25,-

the lower corner of the shovel still engages the pcripheries of the guiding pilot wheels 35, as shown in Fig. 6, but on further advance, the shovel clears the pilot wheel and swings inwardly as it passes up over the drive wheels 27 until the back of the shovel engages the bottom of the shovel next in advance. The shovel thus recedes gradually from the vertical portion of the conveyer chute until it clears the pilot wheel. This arrangement prevents any considerable dropping back of coal from the exit pipe. The exit pipe 18 is preferably slightly flared, as shown, so that the successive charges can be readily thrustupwardly into the pipe by the shovels.

In the form shown in Figs. 4, 5 and 7, the movable carrierv for the shovels comprises a pair of rotating drive wheels 43 upon which the shovels are directly mounted. These drive wheels are loosely mounted upon the transverse shaft or axle 44 which is mounted at its ends in a pair of standards 44', which rise from the base plate of the ash pit 12. The wheels 43v a're connected by a series of through-bolts 45* arranged adjacent their peripheries, andzwhich serve as transverse axles or pivots upon which the feathering shovels 46 are hung. The Stoker casingy comprises side walls 47, connected by bolts 48 extending through space bars 49, and top and bottom curved pieces 50 and 51. The stoker casing in this formV is narrower than in the construction shown in Figs. l to 3, inclusive, and the lower portion thereof forms the conveyer chute from thehopper 21 to the exit pipe 18. The hopper and exit pipe are similar in construction to those previously described, and the latter opens into the lower portion of the lire-box 1() through a central opening in the grate 19.

feed chute.

The wheels 43 are arranged within circular openings in the sides 47 of the casing and the shovels carried thereby are arranged to sweepthrough the lower portion of the casing, bridging the space between the wheels and the curved floor 51, and also filling the space between the side walls 47. The shovels are substantially similar in form to those previously described, except that the convex bottom faces thereof are necessarily somewhat longer. Furthermore, it is necessary to arrange the shovels farther apart than in the construction previously described, in which the shovels are mounted on a chain looped over the guiding or pilot wheels. Where they are mounted directly upon the drive wheels, they must be arranged farther apart, in order to provide space for the shovels to swing inwardly as they arrive at the mouth of the exit pipe. To fill the spaces between the adjacent shovels, a series of segmental bridge pieces 52 are employed which are fixed to the edge portions of the wheels 43.

The wheels and shovels are driven from a shaft 53 mounted in suitable bearings in the upper portions o'f the side walls 47 and provided at one end with a gear 54, which meshes with a large gear 55 fixed upon the hub portion of one of the `wheels 43. The movementof the'shovels is controlled by a guide block 56 of segmental form, which is preferably fixed to the shaft or axle 44, and is arranged, as shown, between the lower portions of the drive wheels 43. The outer face of the guideblock is concentric with the axle 44 and with the curved Hoor of the feed chute, and this face coperates with the back portions of the shovels to hold the latter in proper position as they pass through the The shovels, as in the form previously described, are pivotally mounted upon their transverse axles at their inner forward corners. At their inner rear cor` ners, the shovels are preferably provided with anti-friction rollers 57 which are arranged to engage the outer curved face of the guide block 56. As the shovels pass over the axle 44, they tend to swing until in balance from their pivotal points of support. They are prevented. from swinging too far in this direction by a series of stop pins 58 which project inwardly from the wheels 43 and engage the backs of the shovels as they pass over the axis of rotation of the drive wheels. As each shovel approaches the mouth of the hopper, its back engages the rear end of the guide block and it is thrust out into the feed chute to pick up the portion of coal delivered thereto from the hopper 2-1. The shovel is prevented from projecting too far by contact with the curved floor 51 and preferably, also, by the engagement of the rollers 57 thereon with the edges of the bridge pieces 5,2. As the shovels pass vided with an inclined face with which the roller at the rear inner curve or heel of the shovel contacts as the shovel recedes from the delivery end of the feed chute. rlhis face is so arranged that the shovel gradually recedes to thereby prevent a suddendrop of the coal contained in the exit pipe. The shovel recedes as it asses upwardly over the axis of rotation o the drive wheels and, as stated, it is prevented from over turning by the engagement of its back portion with the stop pins 58. As the shovels are necessarily arranged fartherpapart in this form,V

each shovel must carry and move a greater amount of coal with the result that more power is required to operate this form than that shown in Figs. l to 3, inclusive, in which the shovels are mounted upon a chain which islooped'over. the drive wheels and also over guiding or pilot wheels. For this reason, the first form described-is-preferred To vary the point at which theshovels are withdrawn from the feed chute, `the guide bloclr 56 is preferably adjustable. rlhis adj ustment is eectedby shifting the shaft or axle 44 whereon the guide block-is fixed. For this purpose, the shaft, while held stationary in position during the operation of the device, is rotatably mounted in bearings in the upper ends of the standards 44', and is provided at one Yend vwith a crank arm 59. A pin 60 is arranged to Vextend through an opening in the end of the crank arm and engage any one of a series of holes 61 in the adjacent standard 44 to hold the shaft 44 and guide block 56 in adjusted position. ln the extreme member 56, the receding movement of one of the shovels is blocked and the shovels then serve to prevent any backward movement or dropping down of the coal through the exit pipe. It is understood that the guideY is not so positioned as to bloclr the movement of the shovels when the stoker is operated to 1urnish a fresh supply of coal to the fire- It should be noted that in the preferred form shown vin Figs. l, 2 and 6,V and in which.

the shovels are mounted upon chains passing over rotary driving and guiding members, the shovels move in a vertical path through the upper portion of the feed chute immediately below the vertical exit pipe 18,

In this preferred arrangement, any given As each shovel passes upwardly and. de

forward position ofthe guide.

noeaaes Y shovel does `not recedeor withdraw from the upper vertical portion of the feed chute until the next succeeding shovel has com-.

menced to move in a substantially vertical directien. As each shovel moves through the lower curved portion of the feed chute,

it'inerely advances'its individual portion ofy coal and it is moving upwardly in a vertical direction when the Ypreceding shovel recedes and it is required to move not only its individual portion, but all the coal above it in the chute. rlhis arrangement is of advantage, since considerable friction is developed -in attempting to move coal through a curved pipe or chute, but in applicants preferred form, each shovel moves only a small charge of coal through the curved portion of the chute and is not required to force any conl siderable body of coal through the chute until -it is moving upwardly in the vertical portion of the chute and in which the friction is comparatively small.

lt is obvious that-numerous changes may be made in the details set forth. For example, the guiding and pilot wheels in the form shown in Figs. l to 3, inclusive, may be arranged farther apartif it is desired to feed the coalfrom a lower level. Alsothe shovels in this form instead of being nested together, as shown, could be somewhat-smaller and arranged to engage stop pins similar to those shown in Figs. 4 and 5, as they pass over the axis of the drive wheels instead of nesting together in contact. Other changes may be made without departure from the essentials of the invention as defined in the claims.

l claim as my 'invention Lln an under-feed stoker, the combination with a substantially horizontal grate having an opening therein, of an upwardly extending feed Vchute below said grate terminating in a substantially vertical exit pipe leadingupwardly 'to said grate open-- ing, a series of shovels adapted to fit within said feed chute and advance separate charges of coal therethrough and driving and guiding mechanism for moving said shovels in succession upwardly through said chute to thelower end of said vertical exit pipe and then withdrawing ythe same laterally from beneath the mouth of said exit pipe in a direction transverse to the rupward feeding `movement of said shovels.

' 2. In an under-f'eed Stoker, the combination with a substantially horizontal grate havingan opening therein, a feed chute below said grate having a. substantially vertical delivery portion leading upwardly to said grate opening,fa series of sy ovels adapt- `|4`-ed to fit within said chute and Yadvance separate charges of coall therethrough, and driving and guiding means for said shovels arranged to coperate to move the latter in succession upwardly through said chute and then withdraw the same from the vertical delivery portion thereof in a substantially horizontal direction.

3. In an under-feed stoker, the combination with a substantially horizontal grate having a central opening therein, of a feed chut-e below said grate having a lower curved portion and an upwardly extending delivery portion terminating in a short, vertical, flaring exit ipe. a series of shovels adapted to fit within said chute to feed separate charges of coal therethrough, driving-mechanism and guiding means for said shovels arranged to coperate to move the latter in succession through the lower curved and the upwardly extending portions of said chute to the lower end of said exit pipe and then withdraw the same from beneath the mouth of said pipe in asubstantially horizontall direction.

et. In an under-feed stoker, the combination with a substantially horizontal grate having an opening therein, of a feed chute below said grate having an upwardly extending, subst-antially vertical, delivery portion terminating in a short exit pipe leading to said grate opening, a series of shovels adapted to fit within said chute to feed separate charges of coal therethrough and driving and guiding mechanism arranged to coperate to move said shovels upwardly in a vertical path through the vertical delivery portion of said chute to the lower end or mouth of Said exit pipe and then' withdraw the saine from said vertical delivery portion in aV substantially horizontal direction.

5, In an under-feed stoker, the combination with a substantially horizontal grate, of an upwardly extending feed chute below said grate having a Substantially vertical delivery portion leading to saidl grate opening. of a series of feathering shovels adapted to fit within said chute to feed separate charges of coal therethrough, driving meehanism whereon said feathering shovels are pivotally mounted, arranged to move the latter upwardly through said chute to a point below said grate opening and then withdraw the same laterally from said chute, and guiding means for positioning said feathering shovels in said chute to thereby move successive charges of coal upwardly therethrough onto said grate.

6. In an under-feed stoker, the combination with a substantially horizontal grate having an opening therein, of an upwardly extending feed4 chute below said opening terminating in a vertical exit pipe, a series of feathering shovels adapted to fit within said chute to feed separate charges of coal therethrough, driving mechanism whereon said shovels are pivotally mounted, and guiding means for positioning said shovels in said chute, said driving mechanism and guiding means coperating to move said shovels upwardly through said chute` to the lower end of said exit pipe and then permit the backward swinging movement of said pivoted shovels laterally out of said chute in a direction transverse to the upward feeding movement of said shovels.

7. In anunder-feed Stoker, the combination with a substantially horizontal grate having a central opening therein, of a feed chute having a curved lower portion and an upwardly extendingl delivery portion terminating in a short, vertical exit pipe, leading to said grate opening, a series 'of pivotally mounted, feathering shovels, a pair of driving wheels for moving said shovels in an endless path extending through the lower curved and the upwardly extending delivery portions of said chute to the lower end of said exit pipe, and guiding means for positioning said shovels in said chute, said shovels being arranged to swing backwardly in a substantially horizontal direction from beneath the mouth of said exit pipe and into position between said wheels.

8. In an under-feed stoker, the combination with a substantially horizontal grate having an opening therein, of a feed chute below said grate having a substantially vertical delivery portion leading to said opening, a series of feathering shovels, driving mechanism, whereon said shovels are pivotally mounted, arranged to move the latter upwardly through said chute to a point below said grate opening and then withdraw the same laterally from the upper, Vertical delivery portion of said chute, and guiding means for positioning said shovels in said chute and for checking the receding movement of the shovels therefrom.

9. In an under-feed Stoker, the combina tion with the grate having an opening therein, of a feed chute below said grate having a curved lower portion and a substantially vertical delivery portion leading upwardly to said grate opening, a series of feather-ing shovels adapted to tit within said feed chute, a pair of chains whereon said shovels are pivotally mounted, rotary driving and guiding members for said chains and shovels arranged to move the latter through the lower curved portion of said chute and upwardly in a substantially vertical direction through the delivery portion thereof, to a point below said grate opening, said shovels being arranged to swing laterally out of the upper, vertical delivery portion of said chute.

l0. In an under-feed Stoker, the combination with a grate having an' opening therein, of a feed chute below said grate leading upwardly to said opening, a series of feathering shovels adapted to fit within said chute, a pair of chains whereon said shovels are pivotally mounted, rotary driving and guiding tending between the same,

members for said ,chains and shovels arranged 4one above the other and adapted to move' said shovels upwardly through said chute to a point below said grate opening, said upper rotary member Comprising a pair of wheels,4 and said shovels being arranged to swingv laterally out of the upper delivery portion of vsaid chute into position between said wheels.

11. In an under-feed Stoker, the `combination with a grate having a central opening, of a feed chute having a curved lower portion and an upwardly extendin delivery portion terminating in' a 'substantially vertical exit pipe leading to the opening of said grate, a pair of drive wheels, parallel chains passin over said wheels, feathering shovels pivota ly hung. on said chains and `av pilot wheel below said drive wheels over which said shovels pass, said pilot wheel being ar"- ranged to hold 'said shovels-in position as they are advanced by said `drive wheels through said chute, and said shovels being arranged to swing laterally from beneath the mouth of said exit pipe and into position between said drive whee-s.

12. In an under-feed Stoker, the combination with a grate having a central opening, of a feed chute having a curved lower portion and an upwardly extending, substantially vertical delivery portion terminating in an exit pipe leading to said grate opening, of a pair of drive wheels, chains passing over said wheels and having cross-axles ex eathering shovels hung on said cross-axles, and a pilot wheel below said drivin wheel over which said shovels pass, said pilot wheel bein arranged to engage and hold said shove s in position as they are advanced through the lower curved portion of said chute, and fixed guides for engaging the ends of said cross-axles as said shovels move upwardly from said pilot wheel through then wardly extending, delivery portion of said c nte.

noaaaea 13. ln an under-feed Stoker, the combinavtion with a substantially horizontal grate having an opening therein, of a feed chute below said grate having a substantially vertical delivery portion leading to said opening, of a series of feathering shovels, an endless conveyer whereon said shovels are mounted, andA rotary driving and iding wheels arranged one above the other or said conveyer and said shovels arranged to move the latter upwardly ythrough the vertical delivery portion of said chute to a point below 'saidI grate opening and thenwithdraw the same laterally from the vertical delivery portion of the chute.

14. In an under-feed stoker, the combination with a' grate having an opening therein, of a feed chute below said grate having a lower curved portion, and a substantially Y vertical delivery portion leadin upwardly to said grate opening, a series ot feathering shovels adapted to fit within said feed chute to move 'separate charges of coal there-k through, a pair of chains whereon said shovels arev pivotally mounted, and driving and' guiding means for 4moving said shovels through the lower curved portion of said chute and upwardly through the vertical delivery portion thereof to a point below said grate opening, and then permitv the `backward swinging movement of said shovels in lateral direction from the. upper delivery portion of the chute, said driving and guiding means comprising an upper pair of drive wheels for said'chains and a lwer rotary guide wheel arranged to ositively position the shovels within Said c nte and to checktlie recedin movement of the shovels from the upper elivery portion of the chute.

ELEANOR HAGnNow, HARRY L. CLAPR 

